Superconductors made from germanium, a material traditionally used for computer chips, have the potential to revolutionize quantum computing by enhancing reliability and performance in the future.

Superconductors are materials that enable electricity to flow without resistance, making them ideal for various electrical applications, particularly in maintaining quantum coherence—essential for effective quantum computing.

Nonetheless, most superconductors have been specialized materials that are challenging to incorporate into computer chips. Peter Jacobson and his team at the University of Queensland, Australia, successfully developed a superconductor using germanium, a material already prevalent in the computing sector.

The researchers synthesized the superconductor by introducing gallium into a germanium film through a process called doping. Previous experiments in this area found instability in the resulting combination. To overcome this, the team utilized X-rays to infuse additional gallium into the material, achieving a stable and uniform structure.

However, similar to other known superconductors, this novel material requires cooling to a frigid 3.5 Kelvin (-270°C/-453°F) to function.

David Cardwell, a professor at the University of Cambridge, notes that while superconductors demand extremely low temperatures, making them less suitable for consumer devices, they could be ideally suited for quantum computing, which also necessitates supercooling.

“This could significantly impact quantum technology,” says Cardwell. “We’re already in a very cold environment, so this opens up a new level of functionality. I believe this is a clear starting point.”

Jacobson highlighted that previous attempts to stack superconductors atop semiconductors—critical components in computing—resulted in defects within their crystal structure, posing challenges for practical applications. “Disorder in quantum technology acts as a detrimental effect,” he states. “It absorbs the signal.”

In contrast, this innovative material enables the stacking of layers containing gallium-doped germanium and silicon while maintaining a uniform crystal structure, potentially paving the way for chips that combine the advantageous features of both semiconductors and superconductors.